Invaders is a Space Invaders clone, that tries to be as accurate a colour version as is possible on the ZX Spectrum. The player has three ships to spend with four bases to hide behind and must destroy the invading alien army before they get to the Earth. The rows of aliens begin at the top of the screen and the player controls his ship on the bottom of the screen and has try to shot as many as possible down. After all the aliens are shot down another level will be entered which has more and tougher aliens. From time to time a flying saucer appears at the top of the screen. Shooting this down gives the player extra points.